Number Sense & Ratios Review Wednesday, September 3rd, 2014 Number Sense & Ratios Review

Rounding Numbers If the number you are rounding to is followed by 0, 1, 2, 3, or 4, you will round down eg. 38.4 would be rounded to 38 If the number you are rounding to is followed by 6, 7, 8, or 9, you will round up eg. 38.6 would be rounded to 39 If the number you are rounding to is followed by a 5* and only a 5, you will round up or down to the nearest EVEN number eg. 37.5 and 38.5 would both be rounded to 38

Practice 1. Round to the nearest tenth. 45.67 2.93 142.988 45.67 2.93 142.988 2. Round to the nearest hundred. 1467 3934 2658

Percents A number that is calculated “out of 100” eg. 45% can be expressed as 45 100 or 0.45 Express each percent as a fraction in lowest terms. 60% 27% 85%

Fractions as Percents To express a fraction as a percent, first change the fraction to a decimal. eg. 1 2 = 0.50 Next, multiply the decimal by 100. eg. 0.50 x 100 = 50% Express each fraction as a percent. 45 60 15 35 16 32

Ratios Ratios are a method of comparing two qualities. eg. 4:3 would be read as 4 to 3 To reduce ratios to lowest terms you must determine the greatest common factor (GCF) and divide each number by the GCF 24:30 12:48 6:14